Vertical speeds which are precisely zero are not plotted, as is the case for GEM data in 2015.

Earthquakes Data Source

Earthquake location data comes from the United States Geological Survey (USGS).
You can search their catalog with the USGS Earthquake Search.
There are three sets of earthquakes from this source: 4200 North American earthquakes with magnitudes of 4.5 or more,
6387 earthquakes in the western U.S. (lower 48 states) with magnitudes of 3.5 or more, and 10286 global earthquakes of magnitude 5.5 or more, all sets for the years 1995
through 2014.
How many earthquakes are shown depends on the "How many markers displayed" choice.
Color indicates depth of earthquakes (see the Key above).
To find recent earthquakes, see Earthquakes from the USGS Earthquake Hazards Program.

Faults Data Source

From the USGS web site, Quaternary Faults.
Faults are grouped by age, labeled with geological period names:
Historic (younger than about 150 years), Late Quaternary (younger than 130,000 years), Mid to Late Quaternary (younger than 750,000 years).
All faults in an age group are always shown, regardless of the "How many markers displayed" choice.

If you have questions about the data values, please check with the data providers listed above.
Ask UNAVCO
(send mail to: dataunavco.org )
about this map tool and its displays.